Method of extracting properties of a layer on a wafer

Patent metadata

Field	Value
Publication number	US-12469750-B2
Application number	US-202318202650-A
Country	US
Kind code	B2
Filing date	May 26, 2023
Priority date	Oct 25, 2022
Publication date	Nov 11, 2025
Grant date	Nov 11, 2025

Abstract

Provided is a method of extracting properties of a layer on a wafer, the method including emitting electromagnetic waves to a lower surface of the wafer, detecting a first electromagnetic wave, that passes through a target layer on an upper surface of the wafer, and a second electromagnetic wave, that is reflected from the target layer, among the electromagnetic waves to obtain data including information about the first electromagnetic wave and the second electromagnetic wave, and separating a first pulse of the first electromagnetic wave and a second pulse of the second electromagnetic wave from each other in the data and obtaining property data of the target layer.

First claim

What is claimed is:

1 . A method of extracting properties of a target layer on a wafer, the method comprising:
emitting electromagnetic waves to a lower surface of the wafer; detecting a first electromagnetic wave, that passes through the target layer on an upper surface of the wafer, and a second electromagnetic wave, that is reflected from the target layer, among the electromagnetic waves to obtain data comprising information about the first electromagnetic wave and the second electromagnetic wave; and separating a first pulse of the first electromagnetic wave and a second pulse of the second electromagnetic wave from each other in the data, and obtaining property data of the target layer.

2 . The method of claim 1 , wherein the emitting the electromagnetic waves comprises emitting the electromagnetic waves in a direction perpendicular to the lower surface of the wafer.

3 . The method of claim 1 , wherein the detecting the second electromagnetic wave comprises reflecting an electromagnetic wave among the electromagnetic waves, passing through the target layer, toward the target layer.

4 . The method of claim 1 , wherein the detecting the first electromagnetic wave and the second electromagnetic wave comprises simultaneously detecting the first electromagnetic wave and the second electromagnetic wave.

5 . The method of claim 1 , wherein the obtaining the property data of the target layer comprises:
obtaining a first transmission coefficient of the target layer with respect to the first electromagnetic wave; obtaining a second transmission coefficient of the target layer with respect to the second electromagnetic wave from the first transmission coefficient; and dividing the second transmission coefficient by the first transmission coefficient.

6 . The method of claim 5 , wherein the first transmission coefficient is obtained based on variables comprising a transmission coefficient of the target layer, a transmission coefficient of the wafer, an absorption amount of the electromagnetic waves of the wafer and a quantity of electricity of the electromagnetic waves.

7 . The method of claim 6 , wherein the second transmission coefficient is obtained based on variables comprising the variables used for obtaining the first transmission coefficient and a reflection coefficient of a reflector configured to reflect an electromagnetic wave among the electromagnetic waves to the target layer.

8 . The method of claim 5 , wherein the obtaining the property data of the target layer further comprises obtaining a surface resistance of the target layer from a value obtained by dividing the second transmission coefficient by the first transmission coefficient.

9 . The method of claim 1 , wherein a layer is interposed between the wafer and the target layer.

10 . A method of extracting properties of a target layer on a wafer, the method comprising:
emitting electromagnetic waves to a lower surface of the wafer in a direction perpendicular to the lower surface of the wafer; simultaneously detecting a first electromagnetic wave, that passes through a layer and the target layer sequentially formed on an upper surface of the wafer, and a second electromagnetic wave, that is reflected from the target layer, among the electromagnetic waves to obtain data comprising information about the first electromagnetic wave and the second electromagnetic wave; separating a first pulse of the first electromagnetic wave and a second pulse of the second electromagnetic wave from each other; obtaining a first transmission coefficient of the target layer with respect to the first electromagnetic wave from the separated first pulse and the second pulse; obtaining a second transmission coefficient of the target layer with respect to the second electromagnetic wave from the first transmission coefficient; and dividing the second transmission coefficient by the first transmission coefficient.

11 . The method of claim 10 , wherein the first transmission coefficient is obtained based on variables comprising a transmission coefficient of the target layer, a transmission coefficient of the wafer, an absorption amount of the electromagnetic waves of the wafer and a quantity of electricity of the electromagnetic waves.

12 . The method of claim 11 , wherein the second transmission coefficient is obtained based on variables comprising the variables used for obtaining the first transmission coefficient and a reflection coefficient of a reflector configured to reflect an electromagnetic wave among the electromagnetic waves, that passes through the target layer, to the target layer.

13 . The method of claim 10 , further comprising obtaining a surface resistance of the target layer from a value obtained by dividing the second transmission coefficient by the first transmission coefficient.

14 . A method of extracting properties of a target layer on a wafer, the method comprising:
emitting electromagnetic waves to a lower surface of the wafer; detecting a first electromagnetic wave, that passes through the target layer on an upper surface of the wafer, and a second electromagnetic wave, that is reflected from the target layer, among the electromagnetic waves to obtain data comprising information about the first electromagnetic wave and the second electromagnetic wave; and separating a first pulse of the first electromagnetic wave and a second pulse of the second electromagnetic wave from each other in the data, and obtaining property data of the target layer, wherein the emitting the electromagnetic waves comprises emitting the electromagnetic waves in a direction perpendicular to the lower surface of the wafer, and wherein the detecting the second electromagnetic wave comprises reflecting the electromagnetic wave passing through the target layer toward the target layer.

15 . The method of claim 14 , wherein the detecting the first electromagnetic wave and the second electromagnetic wave comprises simultaneously detecting the first electromagnetic wave and the second electromagnetic wave.

16 . The method of claim 14 , wherein the obtaining the property data of the target layer comprises:
obtaining a first transmission coefficient of the target layer with respect to the first electromagnetic wave; obtaining a second transmission coefficient of the target layer with respect to the second electromagnetic wave from the first transmission coefficient; and dividing the second transmission coefficient by the first transmission coefficient.

17 . TThe method of claim 16 , wherein the first transmission coefficient is obtained based on variables comprising a transmission coefficient of the target layer, a transmission coefficient of the wafer, an absorption amount of the electromagnetic waves of the wafer and a quantity of electricity of the electromagnetic waves.

18 . The method of claim 17 , wherein the second transmission coefficient is obtained based on variables comprising the variables used for obtaining the first transmission coefficient and a reflection coefficient of a reflector configured to reflect an electromagnetic wave among the electromagnetic waves, that passes through the target layer, to the target layer.

19 . The method of claim 16 , wherein the obtaining the property data of the target layer further comprises obtaining a surface resistance of the target layer from a value obtained by dividing the second transmission coefficient by the first transmission coefficient.

20 . The method of claim 14 , wherein a layer

Assignees

• Samsung Electronics Co Ltd

Inventors

• Baek Inkeun
• Park Suhwan
• Jeon Ikseon
• Koo Namil
• Kim Ingi
• Kim Jaeho
• Park Junbum
• Jun Sunhong

Classifications

• H10P74/203 Primary

  Structural properties, e.g. testing or measuring thicknesses, line widths, warpage, bond strengths or physical defects · CPC title

• G01N21/9501

  Semiconductor wafers (manufacturing processes per se of semiconductor devices implementing a measuring step H10P74/20) · CPC title

• G01N21/59

  Transmissivity (G01N21/25 takes precedence) · CPC title

• G01N21/55

  Specular reflectivity · CPC title

• G01R31/2831

  Testing of materials or semi-finished products, e.g. semiconductor wafers or substrates (G01R31/318511 takes precedence; testing during manufacture H10P74/00) · CPC title